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An Encyclopedia of the History of Technology part 55

An Encyclopedia of the History of Technology part 55. This one of a kind encyclopedia presents the entire field of technology from rudimentary agricultural tools to communication satellites in this first of its kind reference source. Following an introduction that discusses basic tools, devices, and mechanisms, the chapters are grouped into five parts that provide detailed information on materials, power and engineering, transportation, communication and calculation, and technology and society, revealing how different technologies have together evolved to produce enormous changes in the course of history | PART THREE TRANSPORT Figure 10.2 A Flemish ship of c. 1560. later similar sails were set between the masts. Other improvements came with the increasing size of ships and with the need to carry more sails for greater speed individual sails became larger and increased from one or two to three or four on each mast by 1800. The masts themselves becoming loftier and more square in proportion soon outran the average tree and had to be assembled from two or three sections one above the other often too the largest sections had to be made from smaller timbers. Sails were cut better and set more tautly to obtain the best from the wind blocks containing pulleys to increase manual capacity when hauling on ropes appeared at an early stage and multiple blocks with metal sheaves and bearing made running rigging easier to work. Changes in hull design also improved the qualities of ships. The basic layout with a deep waist between high castles remained but the forecastle was soon much reduced in height. The aftercastle later known as the poop or quarterdeck remained somewhat more pronounced and provided accommodation for officers and passengers if any. The sheer or fore-and-aft curve of the deck was also gradually reduced which greatly reduced the wind resistance of these ships and made them more weatherly. To accommodate the mizen mast tiller steering had given way in the fifteenth century to the whipstaff a vertical lever which operated a yoke attached to the rudder this in turn was succeeded in about 1710 522 PORTS AND SHIPPING Figure 10.3 A Dutch fluyt of the early seventeenth century. by the wheel and tackles making ships much more manageable. For example in 1700 flag officers of the British navy were still making sure that the great ships were safely in harbour by the end of September but in 1759 Admiral Hawke was able to maintain the blockade of Brest far into November and then fight a decisive battle close inshore in Quiberon Bay in a rising gale. During the period from .